Excellent cars, as are Subarus in general.
The twin turbo is still the same EJ20, 2.0 engine as in the Impreza albeit with 2 turbochargers, available on import only, rated at 280bhp.
All the larger cc engines, 2.5 and 3.0 will most likely be UK based cars. None of the UK cars, after 94/95 are turbocharged.
Only the pre 94 car was the single turbo car, which was rallied with great success, and saw Colin McCrae rise to fame.